The invention relates to apparatus for manipulating garment hangers and like objects, and more particularly to improvements in apparatus for singularizing suspendible portions (such as hooks) of garment hangers. Still more particularly, the invention relates to improvements in apparatus for singularizing suspendible portions (hereinafter called hooks) of objects (hereinafter called garment hangers or hangers) which are supported by an inclined ramp and tend to slide along the ramp under the action of gravity.
It is often necessary to singularize hangers which are transported in a processing machine (e.g., in a garment manufacturing plant or in a cleaning establishment) so that a processing station receives one hanger or one garment-carrying hanger at a time. U.S. Pat. No. 4,276,995 to Jennewein discloses a singularizing apparatus wherein the hooks of garment hangers straddle a downwardly sloping rail and can be singularized by a mobile stop in the rail in conjunction with an mobile intercepting member above the rail. The stop is biased upwardly into the path of movement of oncoming hooks by a first spring, and the intercepting member is biased upwardly and away from operative position by a second spring. A cylinder and piston unit is used to move the intercepting member downwardly when a hanger is to advance beyond the stop whereby the stop is depressed and the foremost hook rides over the depressed stop to be arrested by the intercepting member before the stop is permitted to rise again in order to arrest the next hook. The intercepting member is then lifted by the second spring to release the intercepted foremost hook. The first spring which biases the stop upwardly must be sufficiently strong to enable the rising stop to move the entire series of hooks on the rail upwardly and away from the intercepting member when the stop is permitted to rise in response to lifting of the intercepting member by the second spring. Thus, the force of the first spring must be selected in dependency upon the inclination of the rail, on the combined weight of hangers and garments thereon, and on the total number of hangers on the rail upstream of the stop. If the singularizing apparatus is to be effective for satisfactory singularization of a relatively long series of heavy hangers, the apparatus must employ a rather strong spring for the stop and a strong cylinder and piston unit which is capable of depressing the stop into the rail against the opposition of the first spring. If the apparatus is used for singularization of lightweight hangers, the bias of the first spring is excessive and the energy requirements of the cylinder and piston unit are also excessive. Moreover, the apparatus is out of commission if the first spring breaks or jams, and the frequency of the singularizing operation is dependent on the weight of hangers and of the garments thereon.